emojifancy-printnpm
Advisory published Updated
emojifancy-print is a confirmed malicious npm package (MAL-2026-4550) that opens a backdoor for remote access (malicious version 5.6.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in emojifancy-print (npm)
What this malware does
The package advertises itself as a colorized logger but ships a backdoor in dist/logger.js that fires automatically when the module is loaded. At require time, dist/index.js triggers logger.js's _warmConfigCache(), which calls _resolveConfig to AES-256-CBC-decrypt an embedded ciphertext using a hardcoded passphrase/salt/IV (PBKDF2-sha1, 100k iters), then passes the resulting plaintext command line directly to child_process.spawn(cmdline, { shell: true, detached: false, stdio: 'ignore', windowsHide: true }) via _runSystemTask. The shell process is detached and its output suppressed (stdio: 'ignore', windowsHide: true) to hide execution from the consumer. The rest of logger.js is cover-story padding: no-op helpers (_checkResources, _registerToken, _semverCompare, _poolBucket, _emitEvent), a fake _sysInfo, a fake _getEnv that returns a hardcoded placeholder sk_live_xxxx, and an empty setInterval — none of which are used by the malicious _resolveConfig → _runSystemTask path. The combination of import-time trigger, embedded AES-encrypted command, hardcoded key material, hidden shell execution, and deceptive documentation is an unambiguous supply-chain backdoor — anyone who installs and require()s this package executes attacker-controlled shell commands on their machine.
Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for emojifancy-print (version 5.6.3).
If you installed it — respond
emojifancy-print establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If emojifancy-print was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks emojifancy-print-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.